You're making my mouth water
Seems like the butter would cause a lot of flareups, but I wouldn't rule it out. OJ as a base maybe? That seems to be a popular choice around here in various mops, but we aren't exactly the BBQ capital of the world

A mop I use for Q is 1 part apple cider vinegar to 1 part oil. Kind of like a vinaigrette. I put it in a spray bottle and mist the meat. I used to use butter, but butter can congeal and clog the spray nozzle, but as a mop you keep in a pan and warm on the smoker, butter is a great way to go.

seem to recall something like this, maybe from south carolina, referred to as white BBQ? I don't think it was unlike the ingredients Bob listed, but I'm a little fuzzy on it.

My guess would be you are thinking of Big Bob Gibson's(Decatur Ala.) white BBQ sauce...which is a mayonnaise based sauce, or maybe more correctly stated it contains a lot mayonnaise. His sauce has a large following in mostly Northern Ala....I think. he has restaurants in Ala, and one in.... North Carolina?....I think

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Here in New york state - this is what we used for all our church and fire dept BBq's
always a big hit.

It is great and especially if you can marniate it ahead of time.
Just remenber you can't save the marnate that the chicken has soaked in.
I make a huge batch and store it all summer and take out for each use.
I somtimes will go 1/2 vinegar 1/2 lemon juice
also sometimes i add chopped garlic to the marinate.
you also can find it on the interent under cornell barbque sauce. i think they have a site.

CORNELL BARBECUE SAUCE
(enough for 10 halves)
1 cup cooking oil
1 pint cider vinegar
3 Tablespoons salt ( yes it seems like alot but it isn't when done)
1 Tablespoon poultry seasoning
1/2 teaspoon pepper
1 egg
Beat the egg, then add the oil and beat again. Add other ingredients and stir.
Brush sauce on the broiler halves every few minutes during cooking.
Leftover sauce can be stored in a glass jar
in the refrigerator for several weeks.

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